Camera having a pop up flash unit driven by one direction of a motor

ABSTRACT

A camera has a flash unit which is movable between a retracted position and a projected position and which is provided with an illumination-angle varying mechanism. The camera includes an engagement mechanism for holding the flash unit in the retracted position by engagement. A drive mechanism drives the flash unit in a direction of the projected position when the engagement of the engagement mechanism is released. A transmission system transmits an output rotation of a motor, which serves as a drive source, to each of (i) the illumination-angle varying mechanism, and (ii) the engagement mechanism. The transmission system is driven by a rotation of the motor in a first direction (a) to release the engagement of the engagement mechanism, and (b) to drive the illumination-angle varying mechanism to vary a flash illumination angle. The transmission system is driven by a rotation of the motor in a second direction to perform a camera operation other than a flash unit operation. The camera may also include one or more of a brake member for braking a movement of the flash unit, a clutch for switching a direction of drive transmission, and multiple transmission systems.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a camera which includes a built-inflash unit, or a removably attachable flash unit, capable of movingbetween a projected position and a retracted position and having avariable illumination angle.

2. Description of the Related Art

Various automatic pop-up flash mechanisms have conventionally beenproposed.

For example, in the system disclosed in Japanese Laid-Open PatentApplication No. Sho 62-121428, a flash unit is retained by engagement inthe state of being urged in a pop-up direction, and for a pop-upoperation, the flash unit is released from the retention by engagementby means of an electromagnet.

Such a conventional example, however, has a number of disadvantages. Forexample, since a dedicated actuator is needed such as the electromagnetfor initiating the pop-up operation of the flash unit, an increase incost cannot be avoided and the mechanism cannot be simplified. Also, ifa flash zooming mechanism is to be added, an additional motor or thelike is needed and the size of a camera increases.

Another problem of the conventional example is that when the flash unitis popped up by a spring force, it results in a large bounding impactoccurring at the time of the completion of the pop-up operation.

Japanese Laid-Open Utility Model Application No. Hei 1-157328 proposesthat a flash zooming mechanism and a drive motor therefor areincorporated in a flash unit which is turnable, or movable, between aretracted position and a projected position.

Such a conventional example still has a number of disadvantages. Forexample, since the dedicated motor for driving the flash zoomingmechanism is disposed in the flash unit, costs increase and the size ofthe flash unit itself increases. In addition, the flash unit whoseweight is increased due to the incorporation of the motor must be movedbetween the retracted position and the projected position.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide a cameraof reduced cost and size in which the starting of movement of a flashunit from a retracted position to a projected position and anillumination-angle varying operation are carried out by means of therotation of one motor in one direction.

Another object of the present invention is to provide a camera in whichwhile a flash unit, released from retention by engagement, is being madeto move from a retracted position to a projected position by a springforce, the force of a spring used in an engagement mechanism is utilizedto apply a braking force to the flash unit, thereby mitigating an impactoccurring when the flash unit reaches the projected position and alsopreventing the flash unit from bounding at that position.

Another object of the present invention is to provide a camera in whichan illumination-angle varying mechanism in a flash unit is driven byusing a motor provided for driving an operating mechanism in a camerabody and in which mechanisms to be driven are switched from one toanother by switching the direction of rotation of the motor, whereby thesize, costs and weight of the camera can be reduced.

The above and other objects, features and advantages of the presentinvention will become apparent from the following detailed descriptionof a preferred embodiment of the present invention, taken in conjunctionwith the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an exploded, perspective view diagrammatically showing theconstruction of a camera according to an embodiment of the presentinvention;

FIG. 2 is a cross-sectional view of FIG. 1;

FIGS. 3(A) and 3(B) are diagrammatic perspective views showing themanner in which a holder in FIG. 1 is held;

FIG. 4 is a schematic view illustrating the operation of a zoomingmechanism for a flash unit;

FIGS. 5(A), 5(B) and 5(C) are schematic views illustrating the automaticpop-up operation of the flash unit;

FIGS. 6(A) and 6(B) are views of the shapes of cam portions of the fixedengagement member shown in FIGS. 5(A), 5(B) and 5(C);

FIG. 7 is a block diagram showing the circuit of the embodiment; and

FIG. 8 is a flowchart of the operation of the embodiment.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A preferred embodiment of the present invention will be described belowwith reference to FIGS. 1 to 8.

First, the arrangement of a mechanism according to the presentembodiment will be described with reference to FIGS. 1 and 2, and thedetails and operation of the arrangement will also be described withreference to FIGS. 3(A), 3(B) and 6(A), 6(B). Then, the operationsequence of the arrangement will be described with reference to FIGS. 7and 8.

Referring to FIG. 1, a top cover 1 serves as an exterior member whichconstitutes part of a camera body. A case 2 is supported rotatably withrespect to the top cover 1, and constitutes the skeleton of a flashunit. A slot 2a plays the role of routing a lead wire 40 to be describedlater by allowing it to pass therethrough, and of absorbing the movementof members caused by a flash zooming operation. A flash cover 3constitutes the external appearance of the flash unit, and is fixed tothe case 2. A panel 4 covers the entire front face of the flash unit,and has a Fresnel lens portion 4a for controlling flash light and awindow portion 4b opposing a red-eye preventing lamp which will bedescribed later. A base plate 5 has a plurality of gear shafts, abearing 5a having an outer circumference which serves as a rotatingshaft for the case 2, a bearing 5b and a spring hook 5c. The base plate5 is fixed to the top cover 1 on the reverse side thereof by screws.

A motor M2 is fixed to the camera body or to a mirror box, and a gear 6is meshed with a gear train which is coupled to the motor M2 and whichincludes a planetary clutch mechanism to be described later. Rotation inone direction only is transmitted to the gear 6 from the motor M2through the gear train. The rotation of the gear 6 is rotationallytransmitted to a gear 8 through a gear 7.

A gear 9 is meshed with the gear 8, and is rotatably fitted into theinner circumference of the bearing 5a of the base plate 5. A gear 10 ismeshed with the gear 9, and has a blade assembly 10a on one face. Alever 11 has a shaft portion 11a, a projection 11b, a spring hook 11cand a switch pressing portion 11d, and the shaft portion 11a issupported for rotation with respect to the inner circumference of thebearing 5b. The switch pressing portion 11d turns on a switch SW3 whenthe lever 11 moves for a pop-up operation. A retaining lever 12 has aclaw 12b as well as a projection 12a in the vicinity of the claw 12b,and is fixed to the shaft portion 11a of the lever 11. A spring 13 ishooked on the spring hook 5c of the base plate 5 at one end and on thespring hook 11c of the lever 11 at the other end. The spring 13 urgesthe retaining lever 12 counterclockwise, i.e., so that the claw 12brotates in its engagement direction. A bearing 14 is, in part, fixed tothe top cover 1 and, in part, serves as a rotating shaft for the case 2.

Screws 15L and 15R serve as stoppers when the case 2 rotates in thedirection in which it projects from the top cover 1, and are fastened tothe top cover 1. A spring 16 urges the case 2 in the pop-up direction,and is fitted onto a portion of the outer circumference of the bearing14 with one arm hooked on the screw 15R and the other arm on the case 2.A fixed engagement member 17 has a hook 17a on which the claw 12b of theretaining lever 12 is hooked. As shown in more detail in FIGS. 6(A) and6(B), the fixed engagement member 17 has cam portions 17b and 17c, andthe cam portion 17c has an arc concentric to the rotational axis of thecase 2. The fixed engagement member 17 is fixed to the case 2.

As shown in FIGS. 5(A) to 5(C), when the motor M2 is activated, therotation of the motor M2 is transmitted to the gear 10 through the gears6 to 9 and the blade assembly 10a of the gear 10 presses down theprojection 11b of the lever 11 against the spring 13. Then, theretaining lever 12 is made to rotate in a clockwise direction which isthe same as the direction of movement of the lever 11, and the claw 12bof the retaining lever 12 is released from the hook 17a of the fixedengagement member 17. The case 2 starts to turn in the projectingdirection by the urging of the spring 16, thus bringing the projection12a into abutment with the cam portion 17b of the fixed engagementmember 17.

The case 2 turns further, and as it turns by the force of the spring 16,the case 2 presses the projection 12a of the retaining lever 12 throughthe cam portions 17b to 17c of the fixed engagement member 17. Thus, theretaining lever 12 is made to turn in the region of the cam portion 17cuntil the projection 11b of the lever 11 moves away from the rotatingarea of the blade assembly 10a of the gear 10 (refer to FIGS. 5(B) and5(C)). In other words, the retaining lever 12 is released by the bladeassembly 10a and the case 2 starts its upward movement. The retaininglever 12 is made to escape to a further extent by the upward movement ofthe case 2, and the projection 11b of the lever 11 is made to turnoutward of the rotating area of the blade assembly 10a so that nofurther rotation of the motor M2 is transmitted to either of the lever11 and the retaining lever 12. The case 2 further turns in theprojecting direction until it comes into abutment with the screws 15Land 15R, with a constant frictional force produced between theprojection 12a and the arcuate part of the cam portion 17c by the urgingforce of the spring 13 (refer to FIGS. 5(A) to 5(C)).

A gear 18 is fixed coaxially to the gear 9 positioned within the topcover 1 and transmits a drive force to a mechanism inside of the case 2.Idlers 19 and 20 transmit the rotation of the gear 18 to a gear 21. Thegear 21 has a cam 21a on one face and a contact piece 31 (refer to FIG.2) fixed to the other face. The contact piece 31 is in slidable contactwith a printed board 32 (refer to FIG. 2) to detect the phase of the cam21a. The aforesaid gears 19 to 21 are supported for rotation aboutassociated shafts on the case 2. A transmission lever 22 has a bearingwhich is rotatably fitted onto an associated shaft on the case 2, aroller, or pushing portion 22b, for tracing the motion of the cam 21a,and a pressure part 22a for pressing a holder 27 (refer to FIG. 3(A)). Aspring 23 is fitted onto the outer circumference of the bearing of thetransmission lever 22 with one end hooked on the case 2 and the otherend, on the holder 27 which will be described later. A pressure plate 24is fastened to the case 2 by screws in the state of securing the gears19 to 21 and the transmission lever 22 in position.

A xenon tube 25 is fixed to a reflector 26 by rubber which is not shown.The holder 27 holds the xenon tube 25 and the reflector 26. A holdingmember 28 is fixed in the inside of the case 2. A shaft 29 is held bythe holding member 28 and is positioned to extend in a directionperpendicular to the plane of the panel 4. A rail member 30 has arail-like slot 30a which extends in the same plane as the shaft 29, andis fixed in the inside of the case 2. As shown in FIGS. 3(A) and 3(B),one end of the holder 27 is supported for sliding movement along theaxis of the shaft 29, and the other end has a boss 27b which issupported for sliding movement along the slot 30a in the rail member 30.One end of the spring 23 is hooked on a projection 27a of the holder 27,and the holder 27 is urged toward the panel 4 by the spring 23 and issubjected to a restricting force acting in an opposite direction by thetransmission lever 22.

More specifically, as shown in FIG. 4, the transmission lever 22 is madeto swing on the basis of the cam displacement of the cam 21a of the gear21 to which the rotation of the motor M2 is transmitted. A pushingportion 22b pushes the projection 27a of the holder 27 against thespring 23, thereby causing a flash part made up of the reflector 26 andthe xenon tube 25 held by the holder 27 to move to and fro in oppositedirections perpendicular to the plane of the panel 4.

A red-eye preventing lamp 33 and a reflector 34 for intensifying thelight from the red-eye preventing lamp 33 by reflection are fixed on thereverse side of the window 4b of the panel 4. As shown in FIG. 2, thecase 2 is divided into three sections: and the flash part made up of themembers 25 to 27 is laid out in the middle section; a mechanism partincluding the elements 18 to 24 for driving the flash part, in theleft-hand side section; and a unit made up of the red-eye preventinglamp 33 and the reflector 34, in the right-hand side section. A bundleof lead wires 40 extends through the bearing 14 into the right-hand sidesection of the case 2, and some of the lead wires 40 are connected tothe lamp 33 with the other lead wires connected to the xenon tube 11through the slot 2a.

A planetary clutch mechanism for transmission of the output of the motorM2 will be described below with reference to FIG. 4. An output gear 51of the motor M2 is coupled to a sun gear 53 through a transmission gear52. A planetary lever 54 is frictionally coupled to the central shaft ofthe planetary gear 53, and a planetary gear 55 is rotatably supported bythe planetary lever 54. Thus, the sun gear 53, the planetary lever 54and the planetary gear 55 constitute the planetary clutch mechanism.

Although a detailed illustration is omitted, a mirror driving gear 56 isprovided. As the mirror driving gear 56 rotates in one direction, a mainmirror 60 performs the motion of moving from the observation-enableposition (down position) shown in FIG. 4 to an exposure-enablewithdrawal position (up position) and returning from the exposure-enablewithdrawal position to the observation-enable position.

When the motor M2 is reversed, the sun gear 53 rotates in thecounterclockwise direction to mesh the planetary gear 55 with the gear6. When the motor M2 is forwarded, the planetary gear 55 meshes with themirror driving gear 56.

FIG. 7 is a circuit block diagram showing the present embodiment.

A circuit element PRS performs camera control and consists of a one-chipmicrocomputer (hereinafter referred to as a "microcomputer") including,for example, a CPU (central processing unit), a ROM and a RAM as well asan A/D conversion function. The microcomputer PRS controls a series ofoperations of the camera such as an automatic exposure control function,an automatic focus detecting function, a flash control function, a filmwinding function and a mechanism charging function in accordance with asequence program for the camera which is stored in the ROM.

To achieve the aforesaid control, the microcomputer PRS communicateswith a lens and peripheral circuits provided in the camera body by usingsynchronous communication signals SO, SI and SCLK as well ascommunication selecting signals CLCM, CSDR and CDDR, thereby controllingindividual circuits and the operation of the lens.

Symbol SO represents a data signal outputted from the microcomputer PRS,symbol SI represents a data signal inputted to the microcomputer PRS,and symbol SCLK represents a sync clock for the signals SO and SI. Alens communication buffer circuit LCM supplies electrical power to apower source terminal for the lens during the operation of the camera,and serves as a buffer for communication between the camera and the lenswhen the selecting signal CLCM from the microcomputer PRS is at its highpotential level (hereinafter referred to simply as "H level"). Morespecifically, when the microcomputer PRS sets the selecting signal CLCMto an H level and sends out predetermined data as the signal SO insynchronism with the sync clock SCLK, the buffer circuit LCM outputsbuffer signals such as the sync clock SCLK and the signal SO to the lensthrough camera-to-lens contacts. Similarly, the buffer circuit LCMoutputs as the signal SI a signal indicative of a focal length suppliedfrom the lens. The microcomputer PRS receives the signal SI as data fromthe lens in synchronism with the sync clock SCLK.

A circuit SDR is a drive circuit for a focus-detecting line sensor madeup of a CCD and other sensors. When the communication selecting signalCSDR is at its H level, the drive circuit SDR is selected and iscontrolled by the microcomputer PRS by using the signals SO, SI and theclock SCLK.

A light-measuring sensor SPC for exposure control receives light from asubject through a photographic lens. An output SSPC of thelight-measuring sensor SPC is applied to an analog input terminal of themicrocomputer PRS and, after A/D conversion, is used for automaticexposure control (AE) in accordance with a predetermined program.

A circuit DDR is a circuit for performing switch detection and forproviding display, and when the signal CDDR is at its H level, thecircuit DDR is selected and is controlled by the microcomputer PRS byusing the signals SO, SI and the sync clock SCLK. A circuit FMS is afilm-transportation detecting circuit and its detection output isinputted into the circuit DDR as a signal SFMS. A circuit MES is amechanical-phase detecting circuit for a shutter, a mirror and the like,and its detection output is inputted into the circuit DDR as a signalSMES.

A circuit FLS is a flash-phase detecting circuit, and detects whetherthe flash unit has popped up or determines the phase of the zooming ofthe flash unit, and supplies a detection output to the circuit DDR as asignal SFLS. A switch X is turned on when the running of the leadingcurtain of the shutter is completed, and a switch CN2 is turned on whenthe running of the trailing curtain is completed.

The circuit DDR switches the display contents of a display member DSP ofthe camera or transmits switch or state signals associated with variousstates of the camera to the microcomputer PRS by communication, on thebasis of data transmitted from the microcomputer PRS.

Switches SW1 and SW2 are switches interlocked with a release buttonwhich is not shown. When the release button is depressed to a firststroke position, the switch SW1 is turned on, and subsequently, when therelease button is depressed to a second stroke position, the switch SW2is turned on. When the switch SW1 is turned on, the microcomputer PRSperforms light measurement, automatic focus adjustment, a pop-upoperation of the flash unit and red-eye preventing flashing, as will bedescribed later. When the switch SW2 is turned on to generate a triggersignal, the microcomputer PRS performs exposure control, flashing of theflash unit and film winding. A switch SW3 is a switch for detecting thecompletion of the pop-up operation of the flash unit, and detects themotion of the aforesaid lever 11. A motor M1 is a film transportingmotor, and a motor M2 is a motor for realizing mirror-up and mirror-downoperations, shutter charging, a pop-up initiating operation of the flashunit and driving for flash zooming (variation of an illumination angle).The motors M1 and M2 are driven in the forward and reverse directionsunder the control of associated drive circuits MDR1 and MDR2. SignalsM1F, M1R, M2F and M2R are inputted from the microcomputer PRS to thedrive circuits MDR1 and MDR2 as signals for motor control.

Electromagnets Mg1 and Mg2 are provided for initiating the running ofthe leading curtain and the trailing curtain of the shutter,respectively. The electromagnets Mg1 and Mg2 are respectively energizedby amplifier transistors Tr1 and Tr2 by the application of signals SMG1and SMG2, whereby the shutter is controlled by the microcomputer PRS.

A lamp LAMP is a red-eye preventing lamp and is energized by anamplifier transistor Tr3 by the application of a signal SLAMP, wherebyemission control is provided by the microcomputer PRS.

A circuit FLSH is a flash circuit including a main capacitor and a xenontube, and is controlled by the microcomputer PRS by means of a flashingsignal FS, a flashing stop signal FO, a charging start signal SC and acharging completion signal CF.

A switch SW4 is a switch indicating whether a red-eye preventing mode isset.

The operation of the camera having the above-described arrangement willbe described below with reference to the flowchart of FIG. 8. When apower source switch (not shown) is turned on (Step #1), the supply ofelectricity to the microcomputer PRS is initiated and the microcomputerPRS initiates execution of a sequence program stored in the ROM. Whenthe execution of the sequence program is initiated by the aforesaidoperation, it is detected in Step #2 whether the switch SW1 has beenturned on by the depression of the release button SW1 to the firststroke position. If the switch SW1 is off, the process proceeds to Step#3, where all control flags and control variables set in the RAM of themicrocomputer PRS are cleared and initialized.

Steps #2 and #3 are repeated until the switch SW1 is turned on or thepower source switch is turned off. When the switch SW1 is turned on, theprocess proceeds to Step #4. In Step #4, a light measurement subroutinefor exposure control is executed. An output SSPC from the lightmeasuring circuit SPC shown in FIG. 7 is inputted into the microcomputerPRS through an analog input terminal thereof, and the microcomputer PRSperforms A/D conversion. The microcomputer PRS computes an optimumshutter control value and aperture control value on the basis of thedigital light measurement value and determines whether use of the flashunit is needed, and stores the optimum shutter and aperture controlvalues and the decision result into predetermined addresses within theRAM. In Step #5, an AF operation is completed, and if it is determinedin Step #6 whether the flash unit is needed, the operation of settingthe flash unit to a usable condition is started. Also, during a releaseoperation, control of the shutter and the diaphragm is performed on thebasis of the aforesaid values.

In Step #7, the motor M2 is reversed, and the gears 6 to 10 are made torotate to release the retention provided by the retaining lever 12,thereby causing the flash unit to pop up. Then, the process proceeds toStep #8a, where it is detected whether the flash unit has been popped upby detecting whether the switch SW3 has been turned on. If thecompletion of the pop-up operation is detected, the motor M2 istemporarily stopped in Step #8b. In Step #9, it is determined whetherthe charging of the flash unit has been completed. If the flash unit hasnot yet been completely charged, the process proceeds to Step #10, wherethe microcomputer PRS outputs the charging-of-flash-unit start signal SCto start the charging of the flash unit. If the charging is completed,the charging completion signal CF is generated, and the process proceedsto Step #11. In Step #11, the microcomputer PRS receives information onthe present focal length of the photographic lens via the lenscommunication buffer circuit LCM. Then, in Step #12, the motor M2 isagain reversed. Since the flash unit has previously been popped up bythe reverse drive of the motor M2 in Step #7, a retention releasemechanism withdraws into a non-engagement position and continues idling.Since the projection 11b of the lever 11 is away from the rotating areaof the blade assembly 10a, only a flash zooming mechanism is driven bymotor M2. (the transmission lever 22 is made to swing by the motion ofthe cam 21a, thereby moving the holder 27). A signal from theflash-zooming detecting printed board 32 is transmitted to themicrocomputer PRS via the flash-phase detecting circuit FLS. At the timewhen the flash unit reaches the position of an illumination anglecorresponding to the present focal length of the photographic lens, themotor M2 is reversed. Although not shown, the detecting printed board 32has a pattern corresponding to focal length (cam phase), and the stateof zooming of the flash unit is detected by causing the contact piece 31to slide on the pattern. The process proceeds to Step #13, where thestate of the switch SW4 is identified to determine whether the red-eyepreventing mode has been set. If it is determined that the red-eyepreventing mode has not been set, the process proceeds to Step #17;otherwise, the process proceeds to Step #14.

If the red-eye preventing mode has been set, the lamp LAMP (red-eyepreventing lamp 33) is lit up when the signal SLAMP of the microcomputerPRS of FIG. 7 is at the H level, and illuminates a subject to reduce thepupils thereof, thereby preventing a red-eye phenomenon. Then, theprocess proceeds to Step #15, where it is detected whether the switchSW2 has been turned on by the depression of the release button to thesecond stroke position. If the switch SW2 is off, the process waits forthe switch SW2 to be turned on in Step #15. If the switch SW2 is on, theprocess proceeds to Step #16. It is determined in Step #16 whether thetime period required to reduce the pupils has elapsed. If such requiredtime period has not yet elapsed, the lamp LAMP continues to be lit up.If the required time period elapses, the process proceeds to Step #18.If it is determined in Step #6 that the flashing of the flash unit isnot needed, the process proceeds to Step #17, where it is determinedwhether the switch SW2 has been turned on. If it is determined in Step#13 that the red-eye preventing mode has not been set, the processsimilarly proceeds to Step #17, where it is determined whether theswitch SW2 has been turned on. If the switch SW2 is turned on, theprocess proceeds to Step #18, where a shutter release operation isstarted. More specifically, the motor M2 is driven forward in accordancewith the signal M2F from the microcomputer PRS, and meshes the planetarygear 55 with the mirror driving gear 56 to perform a mirror-upoperation. When the mirror-up operation is completed, the signal SI issent to the microcomputer PRS through the mechanical-phase detectingcircuit MES and the motor M2 is made to stop. Then, the shutter leadingcurtain electromagnet Mg1 is energized in accordance with the signalSMG1 from the microcomputer PRS, and the shutter leading curtain is madeto run by the force of a spring which is not shown, thereby causing filmto be exposed. Subsequently,the signal SMG2 is generated after apredetermined time delay based on the shutter speed computed in Step #4,and the shutter trailing curtain electromagnet Mg2 is energized to causethe shutter trailing curtain to run. If the flash unit is not needed,the shutter speed is set to a flash sync speed. If the flash unit isneeded, the process proceeds to Step #19, where a decision is made as tothe state of an X-sync contact which is turned on when the shutterleading curtain completes running. If the X-sync contact is turned on,the signal is sent to the microcomputer PRS through the circuit DDR and,in Step #20, the flash unit is made to flash (the xenon tube 25 is madeto flash). If the flash unit is not needed, it does not flash. If theflash unit flashes, the flashing stop signal FO is generated on thebasis of the output of a flashing control circuit which is not shown,and the flashing of the flash unit is stopped. Then, the processproceeds to Step #21, where it is determined whether the running of theshutter trailing curtain has been completed. If the running of theshutter trailing curtain has been completed, the switch CN2 is turned onand a corresponding signal is transmitted to the microcomputer PRSthrough the circuit DDR. The process proceeds to Step #22. In Step #22,the motor M2 is driven forward on the basis of the signal M2F to performa mirror-down operation and a shutter charging operation. If themirror-down operation and the shutter charging operation have beencompleted, a corresponding signal is transmitted to the microcomputerPRS through the mechanical-phase detecting circuit MES and the forwardrotation of the motor M2 is stopped. Then, the process proceeds to Step#23, where film transportation is performed. The motor M1 is drivenforward on the basis of the signal M1F from the microcomputer PRS,thereby causing the film to be wound.

When the film is wound by one frame, a corresponding signal istransmitted to the microcomputer PRS through the film-transportationdetecting circuit FMS, and the forward running of the motor M1 isstopped. Incidentally, the motor M1 is arranged to be reversed on thebasis of the signal M1R, causing the film to be rewound. The operationsof Steps #22 and #23 need not necessarily be performed in series and mayalso be performed at the same time.

When the shutter charging and the film transportation have beencompleted, the process proceeds to Step #24, where it is determinedwhether the flash unit has been charged. If the flash unit is notcompletely charged, the process proceeds to Step #25, where charging ofthe flash unit is performed in preparation for the next photographiccycle.

The above-described embodiment has the following features. Since theengagement of the flash unit in the retracted position is released byutilizing a transmission system for driving an illumination-anglevarying mechanism provided in the flash unit, there is no need for anelectromagnet or the like which has conventionally been used forreleasing such an engagement. Accordingly, it is possible to prevent anincrease in the size of a camera and to achieve a reduction in cost.

Both the release of the engagement of the flash unit and the drive ofthe illumination-angle varying mechanism are performed by utilizing therotation of a motor in one direction as one drive source. Therefore,that even after the release of the engagement, the operation ofreleasing the engagement is continued if the illumination-angle varyingmechanism is being driven. However, such an operation is not a problemsince a pushing member and a pushed member, which is pushed duringdriving, are moved away from each other in an interlocked relation bymovement of the flash unit toward the projected position after therelease of the engagement.

Since the rotation of the motor in another direction can be utilized asa drive source for the elements other than the flash unit, it is notnecessary to add another motor for the flash unit alone.

Although the above embodiment has been described with reference to theflash unit of the type which is built in a camera body, the presentinvention can also be applied to a flash unit of the type which isremovably attachable to a camera body. In the case of the latter type offlash unit as well, even if the position of the flash unit variesbetween the pop-up position (projected position) and the down position(retracted position), the transmission system is not adversely affectedsince the axis of rotation of the flash unit is coincident with thecentral axis of a transmission gear.

Although the above-described embodiment employs gears for thetransmission system, a belt drive mechanism may also be employed.

In the above-described embodiment, a turnable retaining lever and aretention releasing device are provided in the camera body, and a fixedengagement claw is provided in the flash unit. However, if the sides onwhich these members are provided are reversed, it is possible to achievesimilar advantages.

According to the above-described embodiment, a camera includes abuilt-in flash unit, or a removably attachable a flash unit, which isturnable between a retracted position and a projected position withrespect to a camera body and which is provided with anillumination-angle varying mechanism. The rotation of a motor in onedirection is utilized as a drive source both to release the engagementof the flash unit in the retracted position and to drive theillumination-angle varying mechanism. Accordingly, there is provided acamera of reduced size and cost without the use of an electromagnetwhich has conventionally been employed.

According to the above-described embodiment, there is also provided acamera in which the force of a spring used in a flash-unit engagementmechanism is utilized to apply a braking force to the movement of theflash unit by a spring force from the retracted position to theprojected position, thereby mitigating the impact caused by a pop-upoperation.

According to the above-described embodiment, a camera includes abuilt-in flash unit, or a removably attachable flash unit, having anillumination-angle varying mechanism in its interior. A motor fordriving a camera-operating mechanism such as a mirror and a shutter isused within a camera body to drive the illumination-angle varyingmechanism in the flash unit, and mechanisms to be driven are switchedfrom one to another in accordance with the direction of rotation of themotor. Accordingly, it is possible to realize a reduction in the overallsize of the camera and reductions in the size and weight of the flashunit, and it is also possible to provide a camera which can selectivelyperform the independent operation of the camera-operating mechanism orthat of the illumination-angle varying mechanism.

What is claimed is:
 1. A camera including a flash unit movable between aretracted position and a projected position and provided with anillumination-angle varying mechanism, said camera comprising:(a) anengagement mechanism for holding the flash unit in the retractedposition by engagement; (b) a drive mechanism for driving the flash unitin a direction of the projected position when the engagement of saidengagement mechanism is released; (c) a motor serving as a drive source;and (d) a transmission system for transmitting an output rotation ofsaid motor to each of (i) the illumination-angle-varying mechanism, and(ii) said engagement mechanism, wherein said transmission system isdriven by a rotation of said motor in a first direction (a) to releasethe engagement of said engagement mechanism so that said drive mechanismdrives the flash unit toward the projected position independent of saidtransmission system, and (b) to drive the illumination-angle varyingmechanism to vary a flash illumination angle, and wherein saidtransmission system is driven by a rotation of said motor in a seconddirection to perform a camera operation other than a flash unitoperation.
 2. A camera according to claim 1, wherein said engagementmechanism includes a drive converting mechanism, comprising a pushingmember and a pushed member, for releasing the engagement of the flashunit, said pushing member pushing said pushed member in accordance witha drive force transmitted by said transmission system, to release theflash unit from engagement.
 3. A camera according to claim 2, whereinwhen said pushing member pushes said pushed member to release the flashunit from engagement, said engagement mechanism moves said pushed memberaway from a moving area of said pushing member in an interlockedrelation to a movement of the flash unit toward the projected position.4. A camera according to claim 1, wherein the flash unit is rotatablysupported substantially at a middle position of a top cover of a camerabody.
 5. A camera according to claim 4, wherein said transmission systemtransmits the output rotation of said motor to each of said engagementmechanism and the illumination-angle varying mechanism through a gearhaving a turning axis which coincides with a turning axis of the flashunit.
 6. A camera according to claim 1, wherein the illumination-anglevarying mechanism varies the flash illumination angle by moving aflashing element relative to a lens.
 7. A camera according to claim 1,further comprising a light-emitting element provided in the flash unitfor preventing a red-eye phenomenon.
 8. A camera according to claim 1,wherein said motor drives a camera-operating mechanism by means ofrotation in the second direction.
 9. A camera according to claim 1,wherein said drive mechanism includes a drive spring, the flash unitbeing driven from the retracted position to the projected position by aforce of said drive spring.
 10. A camera according to claim 1, whereinan operation of releasing the engagement of the flash unit by saidengagement mechanism, and an operation of varying the flash illuminationangle by the illumination-angle varying mechanism are performedsubstantially in series.